A person other than the United States, an Indian tribe recognized as such by the federal government, the state, a subdivision of the state, or a municipal corporation or an agency of such a unit of government shall not release salmon or steelhead trout into the public waters of the state and subsequently to recapture and commercially harvest such salmon or trout. This section shall not prevent any person from rearing salmon or steelhead trout in pens or in a confined area under circumstances where the salmon or steelhead trout are confined and never permitted to swim freely in open water.